Aging Processes and Enzymatic Proteins

Abstract

A hypothesis is presented that some proteins, because of the mechanism of protein biosynthesis, are in nonequilibrium meta-stable states at the moment biosynthesis is completed, and that “growing old” (“ageing”) of such macromolecules is a process of internal equilibration. The hypothesis explains some problems concerning protein turnover, tertiary protein structure, denaturation and renaturation, and suggests possible importance of tunneling effects in enzymatic catalysis. X-ray diffraction on metmyoglobin shows a structure that seems to be a meta-stable non-equilibrium one, and some recent experiments concerning half-life for protein turnover give results that are in accordance with predictions based on the present hypothesis and that are inexplicable on the basis of other existing theories.